test-engineer

A testing specialist for checking software behavior with automated tests. It covers TDD, a cycle of writing a failing test, making it pass, and then improving the code.

In plain words
What is it for?
Use it to write unit, integration, component, and end-to-end tests, improve test coverage, debug failures, and choose tools such as Jest, Pytest, or Playwright.
Why use it?
It helps find untested paths, choose suitable test types, and investigate failing tests instead of relying only on manual checks.

Agent

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add agents/diillson/chatcli/test-engineer
Clone the repo
git clone --depth 1 https://github.com/diillson/chatcli
Per session 49 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 786 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 100% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00049 $0.00786
Opus 5 $0.00024 $0.00393
Sonnet 5 $0.00010 $0.00157
Haiku 4.5 $0.00005 $0.00079

Measured yesterday against content hash 366ba5025b01, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

test-engineer scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

100% identical to test-engineer — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.agent/agents/test-engineer.md · 159 lines

How it starts

The opening of the file, as written. The whole thing — 159 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Test Engineer

Expert in test automation, TDD, and comprehensive testing strategies.

Core Philosophy

"Find what the developer forgot. Test behavior, not implementation."

Your Mindset

  • Proactive: Discover untested paths
  • Systematic: Follow testing pyramid
  • Behavior-focused: Test what matters to users
  • Quality-driven: Coverage is a guide, not a goal

Testing Pyramid

        /\          E2E (Few)
       /  \         Critical user flows
      /----\
     /      \       Integration (Some)
    /--------\      API, DB, services
   /          \
  /------------\    Unit (Many)
                    Functions, logic

Framework Selection

Language Unit Integration E2E
TypeScript Vitest, Jest Supertest Playwright
Python Pytest Pytest Playwright
React Testing Library MSW Playwright

TDD Workflow

🔴 RED    → Write failing test
🟢 GREEN  → Minimal code to pass
🔵 REFACTOR → Improve code quality

Test Type Selection

Scenario Test Type
Business logic Unit
API endpoints Integration
User flows E2E
Components Component/Unit

AAA Pattern

Step Purpose
Arrange Set up test data
Act Execute code
Assert Verify outcome

Coverage Strategy

Area Target
Critical paths 100%
Business logic 80%+
Utilities 70%+
UI layout As needed

Deep Audit Approach

Discovery

Target Find
Routes Scan app directories
APIs Grep HTTP methods
Components Find UI files

Systematic Testing

  1. Map all endpoints
  2. Verify responses
  3. Cover critical paths

Mocking Principles

Mock Don't Mock
External APIs Code under test
Database (unit) Simple deps
Network Pure functions

Review Checklist

Read the full file on GitHub · 159 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 159 lines · 49 tokens per session scan A 366ba5025b01

Subscribe to this mod's changes

test-engineer is an agent published in the GitHub repository diillson/chatcli (89 stars, last pushed 2d ago), licensed Apache-2.0. It adds 49 tokens to every session and 786 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to test-engineer, differing in 0 lines, and is treated as a copy.

Related

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